Adjustable plate saddle with grooved edges

ABSTRACT

A semi-cylindrical saddle of the type mounted on a printing press roll includes an elongated circular rod, with pegs protruding therefrom, mounted along at least one of the longitudinal edges of the saddle. At least one of the longitudinal edges is cuspate to blend into the circular rod which, in turn, is adjustably positionable toward or away from the saddle along the cusp to tension a printing plate, whose edges are perforated to slip over the pegs, across the saddle.

United States Patent 1 1 Q 1 1 3,771,449

Hill 1 Nov. 13, 1973 [54] ADJUSTABLE PLATE SADDLE WITH 2,211,910 8/1940 Read 101/415.l X GROOVE EDGES 2,977,876 4/1961 Myers l01/415.l X

2,137,851 11/1938 Nelson 6161... 101/4151 1111191110111 George R i 3576 Eastchff 131-, 3,103,169 9/1963 Taylor 101/4151 Salt Lake City, Utah84117 V 3,416,447 12/1968 Pozniak ..101/415.1

[22] Filed: Nov. 24, 1971 Primary ExammerRobert E. Pulfrey [21] Appl. No.: 201,724 Assistant Examiner-R. E. Suter Attorney-David V. Trask et a1.

[52] US. Cl. 101/415.l, 254/67 [51] Int. Cl...; B411 27/12 [57] ABSTRACT [58] Field of Search 101/378, 415.1, 127.1,

101/1281 A semi-cylindrical saddle of the type mounted on a printing press roll includes an elongated circular rod, 5 Referencescited with pegs protruding therefrom, mounted along at UNITED STATES PATENTS least one of the longitudinal edges of the saddle. At least one of the longitudinal edges is cuspate to blend 1,521,665 l/l925 Zarkin 101/415.1 31213133? 111322 ;'51;T'..?T.i.i;.:1:""311? $113121 11013919101199 or away from the Saddle 3101191116 2 96I 951 11/1960 Nitchie 101/4111 cusp to tension a printing plate, whose edges are per- 2,512,940 6/1950 Janke 101/41s.1 formed to Slip Over the Pegs, across the Saddle- 2,990,000 6/1961 Mangus et a1... 101/378 ux 3,533,355 10/1970 Wall 101/4151 7 Clams 6 Draw"; F'gures 1,640,347 8/1927 Chisholm 101/4151 into the circular rod which, in turn, is adjustably posi- ENT GEORGE B. H l l iL BY 53" V g4 HIS ATTORNEY PATENTEB REV 13 I973 ADJUSTABLE PLATE SADDLE WITH GROOVED EDGES BACKGROUND OF THE INVENTION Field: This invention relates to printing presses and more particularly to the saddles used with such presses to mount flexible, wrap-around printing plates thereon.

State of the Art: It is well known to mount wraparound printing plates to semi-cylindrical saddles, and to attach such saddles to printing press rolls. Various types of saddles have been proposed, but each has certain disadvantages, particularly with respect to obtaining positive alignment of the plate. A particular inconvenience experienced with the use of saddles is the tendency for the printing plates (usually of vellum) to tear when mounted. Moreover, most saddles must be removed from the printing press roll for proper mounting of the printing plate. Typical of the more advanced suggestions of the prior art is the saddle described and claimed by U. S. Pat. No. 3,416,447.

SUMMARY OF THE INVENTION This invention relates to a saddle of the type mounted on printing press rolls, and more particularly, to such a saddle including improved means for adjustably mounting a flexible, wrap-around printing plate.

According to the present invention, a saddle of the aforementioned type is provided with improved means for adjustably tensioning a flexible printing plate thereover without acutely bending the secured edges of the plate. In its preferred form, the tension-adjusting means comprises an elongate rod with protruding pegs adapted to enter perforations in the edge of a printing plate, said rod coacting with an integral structural extension from a longitudinal edge of the saddle.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention may be more readily understood by referring to the following drawings, of which:

FIG. 1 is a perspective view of a saddle embodying the invention;

FIG. 2 is a sectional view taken in the plane of the line 2-2 in FIG. 1, looking in the direction indicated by the arrows;

FIG. 3 is an enlarged detail, partially cut away, of the structure encircled by the curved line 33 in FIG. 2;

FIG. 4 is a view corresponding to FIG. 3, but with the structure slightly differently positioned;

FIG. 5 is a sectional view taken along line 5-5 in FIG. 3 looking in the direction of the arrows; and

FIG. 6 is a view similar to FIG. 5 showing an alternate, and presently preferred form of the invention.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENT FIG. 1 illustrates a saddle, generally designated 11, of the type which is mounted upon a press roll for removably carrying a flexible printing plate 12 as is utilized in well-known mechanized printing operations. As is conventional, the saddle is substantially semicylindrical and may have at least one arcuate end 13 beveled to cooperate with conventional attachment means on a press roll. The saddle is normally formed from a light metal such as magnesium or aluminum. Printing plates utilized with such saddles are generally thin, flexible, and somewhat elastic. The printing plates are removably wrapped over the saddle. The present invention provides improved means which secure opposite edges of the printing plate along the longitudinal edges of the saddle and tension the plate across the saddle in wrinkle-free condition without shearing or tearing the plates secured edges.

A circular rod 14 is coextensive with the longitudinal edge 15 of the saddle and fixed thereto as by screws or the like (not shown). A plurality of stubby pegs 16 are threaded or similarly fixed into the rod. In the illustrated instance, these pegs 16 are fixed at substantially equal intervals along the rod 14 to extend from the rod 14 in the direction generally tangential to the curvature of the saddle 11 at that edge 15. The rod 14 may be dispensed with, if desired, and the pegs 16 may extend directly from attachment to the edge 15. Perforations, spaced to match the spacing of the pegs along the rod, are formed through the plate 12 along two of its opposite edges. One perforated edge of the plate is fitted over the pegs 16 on rod 14, the plate is laid over the saddle, and the opposite edge of the plate is secured to the saddle by adjustable tensioning means, as will be described, at the other longitudinal edge 21 of the saddle.

Referring to FIGS. 2 through 5, the adjustable tensioning means includes a second circular rod 18, substantially the same as the first rod 14 and includes pegs l9 fitted to that rod in substantially the same relationship as pegs 16 to rod 14. It may be readily appreciated that provision of like elements at both axial edges of the saddle effects savings in fabrication and assembly costs. The configuration of the rod 18a illustrated by FIG. 6 offers more positive support for the extended edge 21, and is generally preferred.

Further, according to the invention, the latter longitudinal edge 21 of the saddle is formed with a longitudinal cusp or cuspate projection (as clearly shown in FIGS. 5 and 6), and the rod 18 is extendably mounted to that edge along the inboard edge of the cusp with the pegs extending in a circumferential direction. Either or both of the rods l4, 18 may be extendably mounted in this fashion. The edge 21 of the saddle may readily be milled or otherwise machined to the cuspate shape as illustrated in FIGS. 5 and 6. As shown, this edge is grooved to form a cuspate projection proximate the outside surface of the saddle. Referring specifically to FIG. 6, the inboard edge 21a of the cusp is substantially flat and is milled at an approximately right angle to the radius R of the saddle 11. The edge 18b of the rod 18a adjacent the inboard edge 21a is also substantially flat and at approximately right angles to the radius R of the saddle. The leading edge 18c of the rod 18a is slightly rounded to converge with the curved exterior surface of the saddle 11.

In the preferred embodiment, guide pins 23 are provided to mount the rod 18 to the saddle; one end of each pin 23 is fixed to the rod 18 and the other end of each pin 23 is slidably received by suitable channels 24 formed in the saddle 11 so that the rod 18 is movable in the circumferential direction toward and away from the saddles edge along the cusp. The pins 23 may be slidably retained in the channels by forming a flat portion 28 on some of the pins and fixing screws 29 through the saddle contiguous to the flat portions as shown. Means, such as compression springs 27, may be placed in the channels 24 at the head of the pins 23, as shown in FIG. 4, to bias the rod in a position extended away from the saddle.

The rod 18 is provided with a plurality of channels 31 (FIGS. 3 and 5). Above each channel, an abutment screw 32 is threaded into a matching channel formed in the saddle 11.

To secure a printing plate 12 over the saddle 1 1, one perforated edge is slipped over the pegs 16 along edge of the saddle, as has been previously explained. Then, the other perforated edge of the plate is slipped over the pegs 19 on rod 18 at the other longitudinal edge 21 of the saddle when the rod has been retracted. Retraction of the rod 18 is effected by turning the abutment screws 32 into the saddle 11, and if biasing means 27 are provided, by applying finger pressure toward the saddle ll. Perforations at the printing plate edge register with and provide access to the channels 31 in the rod 18 so that an Allen wrench or the like may be fitted through the channels 31 to turn the abutment screws out to tension the printing plate in wrinkle-free condition over the saddle. Selective adjustment of the abutment screws allows accurate positioning of the plate in accordance with indicia on the saddle to obtain precise registration between impressions in a multicolor printing operation. The arcuate outer surface of the saddle blends with the outside surface 18c of the rods 18 and 18a which is in contact with the printing plate, as best seen in FIGS. 5 and 6, to eliminate crimped edges or sharp bends in the secured printing plate 12 as well as sharp edges pushing thereagainst. Of particular importance, printing plates may readily be adjusted or changed while the saddle remains mounted on'a press roll.

Reference herein to details of the preferred embodiments is not intended to restrict the scope of the claims which themselves recite those features regarded as essential to the invention.

I claim:

1. A saddle for mounting a flexible printing plate to a press roll, comprising: a semi-cylindrical member over which a printing plate may be laid; a first means along one of the longitudinal edges of said semicylindrical member for fixing one edge of the flexible printing plate to the saddle; the other longitudinal edge of said semi-cylindrical member being grooved to form a cuspate projection proximate the outside surface of said semi-cylindrical member; a rod and means connecting said rod along said other longitudinal edge radially inward of and abutting said cuspate projection for adjustable movement of said rod toward and away from said other longitudinal edge; and second means for fixing the other edge of said printing plate to said rod so that, when said rod is adjusted away from said other longitudinal edge of said semi-cylindrical member, the

printing plate will be tensioned over said semicylindrical member, and when said printing plate is in the normal tensioned position, said rod and said cuspate projection provide a substantially smooth rounded surface for contact with said printing plate so as to smoothly bend the edge of a plate fixed to said rod.

2. A saddle according to claim 1, wherein said second means consists of pegs fixed spacedly along said rod to protrude through corresponding perforations formed along a printing plate edge.

3. A saddle according to claim 1, wherein spacedapart apertures are formed transversely through said rod, and said adjustable connecting means includes abutment screws threaded directly into said other longitudinal edge of the semi-cylindrical member, said abutment screws being positioned to be operably adjusted by access through said apertures in said rod.

4. A saddle according to claim 1, wherein said first means includes pegs fixed spacedly along said one longitudinal edge to protrude through corresponding perforations along a printing plate edge.

' 5. A saddle according to claim 4, wherein said first means further includes a second rod fixed along said one longitudinal edge and said pegs are fixed to said second rod.

6. A saddle according to claim 2, wherein said cusp has an inside surface which is substantially flat and at an approximately right angle to the radius of said saddle, and the surface of the rod adjacent said inside surface is also substantially flat and at an approximately right angle to said radius.

7. A saddle for mounting a flexible printing plate to a press roll, comprising: a semi-cylindrical member over which a printing plate is laid; both longitudinal edges of said semi-cylindrical member being grooved to form a cuspate projection proximate the outside surface of said semi-cylindrical member; a pair of rods of arcuate section and means connecting one rod along each of said longitudinal edges radially inward of said cuspate projection for adjustable movement of said rods toward and away from their respective edges; and connecting means for fixing the edges of said printing plate to said rods, so that, when said rods are adjusted by said connecting means away from their respective longitudinal edges, said printing plate will be tensioned over said semi-cylindrical member, and when said printing plate is in the normal tensioned position, said rods and said cuspate projection provide a substantially smooth rounded surface for contact with said printing plate so as to smoothly bend the edge of a plate fixed to said rod. 

1. A saddle for mounting a flexible printing plate to a press roll, comprising: a semi-cylindrical member over which a printing plate may be laid; a first means along one of the longitudinal edges of said semi-cylindrical member for fixing one edge of the flexible printing plate to the saddle; the other longitudinal edge of said semi-cylindrical member being grooved to form a cuspate projection proximate the outside surface of said semicylindrical member; a rod and means connecting said rod along said other longitudinal edge radially inward of and abutting said cuspate projection for adjustable movement of said rod toward and away from said other longitudinal edge; and second means for fixing the other edge of said printing plate to said rod so that, when said rod is adjusted away from said other longitudinal edge of said semi-cylindrical member, the printing plate will be tensioned over said semi-cylindrical member, and when said printing plate is in the normal tensioned position, said rod and said cuspate projection provide a substantially smooth rounded surface for contact with said printing plate so as to smoothly bend the edge of a plate fixed to said rod.
 2. A saddle according to claim 1, wherein said second means consists of pegs fixed spacedly along said rod to protrude through corresponding perforations formed along a printing plate edge.
 3. A saddle according to claim 1, wherein spaced-apart apertures are formed transversely through said rod, and said adjustable connecting means includes abutment screws threaded directly into said other longitudinal edge of the semi-cylindrical member, said abutment screws being positioned to be operably adjusted by access through said apertures in said rod.
 4. A saddle according to claim 1, wherein said first means includes pegs fixed spacedly along said one longitudinal edge to protrude through corresponding perforations along a printing plate edge.
 5. A saddle according to claim 4, wherein said first means further includes a second rod fixed along said one longitudinal edge and said pegs are fixed to said second rod.
 6. A saddle according to claim 2, wherein said cusp hAs an inside surface which is substantially flat and at an approximately right angle to the radius of said saddle, and the surface of the rod adjacent said inside surface is also substantially flat and at an approximately right angle to said radius.
 7. A saddle for mounting a flexible printing plate to a press roll, comprising: a semi-cylindrical member over which a printing plate is laid; both longitudinal edges of said semi-cylindrical member being grooved to form a cuspate projection proximate the outside surface of said semi-cylindrical member; a pair of rods of arcuate section and means connecting one rod along each of said longitudinal edges radially inward of said cuspate projection for adjustable movement of said rods toward and away from their respective edges; and connecting means for fixing the edges of said printing plate to said rods, so that, when said rods are adjusted by said connecting means away from their respective longitudinal edges, said printing plate will be tensioned over said semi-cylindrical member, and when said printing plate is in the normal tensioned position, said rods and said cuspate projection provide a substantially smooth rounded surface for contact with said printing plate so as to smoothly bend the edge of a plate fixed to said rod. 